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Unread 29-03-2010, 12:54
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Ether Ether is offline
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Re: How Do mecanum wheels handle the bumps?

Quote:
Originally Posted by JesseK View Post
Heh, this doesn't look like it has an end in sight.
This is a conversation worth having. It's worth the trouble.

Quote:
I will concede in that the split second before the rollers start to slip there is an instant the wheels put all force directly forward. Yet this split instant of an isolated experiment doesn't translate to assisting a driver in pushing due to the dynamics of the holistic system.
It's not about split-seconds. When a mecanum-wheeled robot is pushing against a brick wall (or any other immobile object) in the forward direction with insufficient torque on its wheels to cause the wheels themselves to turn, then neither are the rollers turning, and 100% (not 71%) of the torque being applied to the wheels must be reacted by the carpet in the plane of the wheels. If the motors are providing 40 in-lbf of torque to each wheel in the forward direction (against the wall), then the carpet reacts with 10 pounds of force on each wheel (on an 8" diameter wheel) in the forward direction in the plane of the wheel, just as it would with a standard wheel. That 10 pounds of force IS the forward component. The forward component is not created by dividing the 10 pounds by the square root of 2.

This is a real-world effect, and it does explain the pushing force of a stalled mecanum-wheeled robot in the forward direction.


~

Last edited by Ether : 29-03-2010 at 13:31.